In his recently published article on Heidegger’s Aesthetics in the Stanford Encyclopedia of Philosophy, Iain Thomson has this to say about Heidegger’s concept of Earth:

“Earth,” in other words, is an inherently dynamic dimension of intelligibility that simultaneously offers itself to and resists being fully brought into the light of our “worlds” of meaning and permanently stabilized therein, despite our best efforts. These very efforts to bring the earth’s “inexhaustible abundance of simple modes and shapes” completely into the light of our worlds generates what Heidegger calls the “essential strife” between “earth” and “world”

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In Heidegger’s view, then, for a great artwork to work—that is, for it to help focus and preserve a meaningful “world” for an audience—this artwork must maintain an essential tension between the world of meanings it pulls together and the more mysterious phenomenon of the “earth.”

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the “earth” is thus Heidegger’s name in 1935–36 for what he most frequently calls “being as such,” a dynamic phenomenological “presencing” (Anwesen) which gives rise to our worlds of meaning without ever being exhausted by them, a dimension of intelligibility we experience both as it informs and as it escapes our attempts to pin it down

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With world and earth, in other words, Heidegger seeks to name and so render visible the quietly conflictual structure at the heart of intelligibility, the unified opposition that allows “being” to be “dis-closed” in time.

Pretty confusing, no? To me, such attempts to make Heidegger intelligible are simply too complex, too philosophical, and too difficult to fully make sense of. Can anyone translate such jargon into plain English? I propose a much simpler explanation of what Heidegger’s concept of “Earth” means: the Earth!

Yes, it really is that simple. “Earth” means the Earth i.e. the planet we live and die on. But note, Heidegger is attempting to describe the subsisting earth which continually and effortlessly surrounds us in nonmetaphysical terms . Thus, “Earth is that which comes forth and shelters.” Examples of “Earth”? A cave to live in, a tree for shade, the ground for walking, materials for building,  ecological mediums for seeing and hearing (light and air), etc. The earth is “that on which and in which man bases his dwelling…In the things that arise, earth occurs essentially as the sheltering agent.” However, “World and earth are essentially different from one another and yet are never separated. The world grounds itself on the earth, and earth juts through world.”

As Being and Time clearly spells out, the “World” in which Dasein lives is different from the planet “on which” we dwell. The world of Dasein is the world of significance given through being-in-a-world i.e. understanding, interpretation and language (as-structure, rift-design, etc.) being-with, possibilities of authenticity, etc. In other words, the “World” of Dasein is our rich cultural-linguistic life and the “Earth” is the always-already-there environment in which we are always already dwelling, indeed, born into.  As Heidegger says, “Upon the earth and in it, historical man grounds his dwelling in the world.”  Accordingly, I interpret the “strife” between earth and world as being characterized by, for example, the tension between hammer-as-physical-thing and hammer-as-tool.

As for the stuff on self-seclusion, this idea is best made sense of in terms of J.J. Gibson’s work on ecological optics. Heidegger, like Gibson, is essentially describing the earth in terms of biological agents and how they interact with the world through perceptual comportment. The earth is self-secluding because due to its three dimensional structure, seeing the book on the table is at the expensive of seeing the table underneath the book. The earth, with its ground, horizons, buildings, and objects, is always occluding some parts of itself from the perspective of a perceiver. There are “lines of sight” embedded in the environment in virtue of the ambient light bouncing off the the ground and various objects and “settling” into stable, overlapping “arrays” which reflect information about the objects and environment being reflected. Gibson describes all this much more rigorously than does Heidegger.

So, for all those confounded by Heidegger’s ideas, do yourself a favor and read Gibson’s  book The Ecological Approach to Visual Perception or his The Senses Considered as Perceptual Systems. Gibson was a much better Heideggerian than Heidegger himself. Getting a sense for what “ecological psychology” entails will provide the conceptual resources for understanding and making sense of Heidegger without all the confusing jargon that does more to obfuscate that illuminate, particularly with a text as complicated and rich as The Origin of the Work of Art.